Can not stop ARM device

We started working with your ADuc7039 evalution board , We successfullyflashed and able ro measure voltage current and Temperature.But yesterday while Debuging I came through theerror. "***Jlink warning:No Matching Core found."I attached the error image File and the code which i have written.

the problem started when i changedPOWKEY0 = 0x1; // Put all peripherals, PLL and Core AsleepPOWCON = 0x00000098;POWKEY1 = 0xf4;